How severe is CVE-2019-1837?

CVE-2019-1837 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2019-1837 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-1837?

CVE-2019-1837 primarily affects Cisco Unified Communications Manager. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-1837?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2019-1837 published?

CVE-2019-1837 was published on 2019-04-18 and last updated on 2026-06-17.

CVE-2019-1837

CVE-2019-1837 is a medium-severity vulnerability in Cisco Unified Communications Manager with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 7.8
EPSS exploit prediction: 2% (82nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Unified Communications Manager
Published: 2019-04-18
Last modified: 2026-06-17

Description

A vulnerability in the User Data Services (UDS) API of Cisco Unified Communications Manager (Unified CM) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the management GUI. The vulnerability is due to improper validation of input parameters in the UDS API requests. An attacker could exploit this vulnerability by sending a crafted request to the UDS API of an affected device. A successful exploit could allow the attacker to make the A Cisco DB service quit unexpectedly, preventing admin access to the Unified CM management GUI. Manual intervention may be required to restore normal operation. Software versions 10.5, 11.5, 12.0, 12.5 are affected.

Frequently asked questions

What is CVE-2019-1837?: A vulnerability in the User Data Services (UDS) API of Cisco Unified Communications Manager (Unified CM) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the management GUI. The vulnerability is due to improper validation of input parameters in the UDS API requests. An attacker could exploit this vulnerability by sending a crafted request to the UDS API of an affected device. A successful exploit could allow the attacker to make the A Cisco DB service quit unexpectedly, preventing admin access to the Unified CM management GUI. Manual intervention may be required to restore normal operation. Software versions 10.5, 11.5, 12.0, 12.5 are affected.
How severe is CVE-2019-1837?: CVE-2019-1837 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2019-1837 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-1837?: CVE-2019-1837 primarily affects Cisco Unified Communications Manager. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-1837?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-1837 published?: CVE-2019-1837 was published on 2019-04-18 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:cisco:unified_communications_manager:10.5\(2.10000.5\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:11.5\(1.10000.6\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:12.0\(1.10000.10\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:12.5\(1.10000.22\):*:*:*:*:*:*:*

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